It’s tough to say if any Star Wars novel is really essential these days. With the full attention of the franchise moved back to movies, and the books firmly placed back in a supporting role, does one really need to read a book like James Luceno’s Catalyst? The answer here is a firm maybe: It entirely depends on your focus within the franchise.
I haven’t seen Rogue One yet (obviously) but my thinking right now is probably not. With Catalyst it’s entirely up to you, your interests, and your focus on the franchise. I still say the only Star Wars novel of the new canon one really needs to read is Bloodline, if only because it sheds some much-need light on the era between Return of the Jedi and The Force Awakens – but then again, that era is my particular interest. Your mileage may vary.
Catalyst begins during The Clone Wars era, and ends an unspecified number of years before Rogue One (and thus A New Hope.) It focuses on the Erso family (Galen, Lyra and their daughter Jyn) and Orson Krennic, as Krennic manipulates Galen into contributing to what will eventually become the Death Star’s planet-destroying laser. Galen is a pacifist, more interesting in using kyber crystals (the very same used in lightsabers) to provide renewable energy than weaponry.
As an infodump and basic backstory, the book works just fine. Luceno has always been one of the Expanded Universe’s more dependable authors, providing fans with something middle-of-the-road readable and Wookieepedia with lots of facts. But as a character piece, the book falls short. Krennic is the most fully-fleshed out character by far, but still feels very stock villain here. We get a sense of Galen and Lyra, but they don’t come alive as characters. Jyn and the book’s biggest original character, Has Obitt, are basically just there because they need to be.
Lyra particularly seems like a wasted opportunity. We know that Galen and Jyn will have their parts to play in the film, and no doubt plenty of screentime. And while we know Lyra appears – we’ve seen her in the trailers – her role may very well be limited. Catalyst may be our best shot to get to know her. And while the character does get some things to do, there’s no spark there.
One of the more interesting – and frightfully relevant – parts of the book is that it does give us an impression of how civilians saw the end of the Clone War and the rise of the Empire. If you’re intrigued about his this first intertrilogy era goes for folks who aren’t already on the fringes of the Rebellion, you could certainly do worse.
So again? Do you need to read it? Right this moment, I would consider two things: Your interest in this particular era and your previous reaction to Luceno’s Star Wars work. (If you’re a big fan of him, no doubt you don’t need my advice and have probably already finished the book, but hey: One never knows.)
But there is a third factor, and that’s Rogue One itself. Does the film adequately present that Galen and Krennic have an extensive history? Or will fans be confused? Is it necessary for one to have this background? That’s rarely been the case in the past – I saw much of the backlash regarding The Force Awakens more a reaction to the heavy tell-not-show environment of the prequel era (and The Clone Wars in particular) than anything else. So my gut instinct is that Catalyst simply details in the wide strokes presented in the film. In any case, we’ll find out.
But for a fan in the here and now? Well, it’s up to you. Luceno is, as always, bland but serviceable enough. There are certainly worse Star Wars books out there, but overall Catalyst doesn’t strike me as anything special.
Grade: 
Another perspective: I had a totally different reaction. The readability was key (this is written like the author is, well, someone capable of and accustomed to writing for an adult audience interested in a decent story, while most of the rest of the new material is…not), and I found it a lot more effective at what it was supposed to to do than Bloodline was. Note that one of my big problems with that book, which at least I both started (putting it ahead of Wendig) and finished (putting it ahead of Battlefront, where I quit after realizing I was halfway through and wasn’t clear on who the protagonist was or why I should care), was that I felt like I was the victim of false advertising. I expected a book mostly about Leia and her relationship to her, well, BLOODline, ie Vader. Instead it’s a meandering demi-plot mostly about characters who are either indifference-inducing or whom I actively end up disliking, in the middle of a political situation that’s never adequately created, explained, or given a history for and worse, we’re thrown into it when it’s clearly starting to fail, which creates a situation rather unfortunately like the prequels, where frankly…who cares if the Republic falls? They’re all idiots, assholes, or both. Good riddance to bad rubbish. The one interesting new character is hauled off to a presumed execution. Let’s make Ransolm relatable, let’s give him the most interesting character development as his relationship with Leia makes him reevaluate, let’s give him an incredibly realistic reaction to Leia’s revelation, and then let’s get rid of him as soon as his viewpoint begins to mature, keep a couple irrelevant, pointless, pilots one of whom’s apparently dying but who cares since that goes nowhere, and waste page time on someone we learned all we needed to know about from Foster’s novelization because we already saw her get vaporized on-screen. Leia spends half her time on a confusing wild-bantha chase involving a Twi’lek (them AGAIN?) with an improbable holo from the part of ROTJ most unrelated to what Bloodline was supposed to be about and sort of vaguely establish SOMETHING that we can’t go into because it’s going to be in the movies. Mostly, the end result was I felt cheated, I’m sorry I bothered, and what generalized sympathy I had seeing Hosnian Prime destroyed is pretty much gone as now I know the characters on it weren’t worth getting invested in.
Plus…honestly, even some of the NJO authors handled the Han/Leia relationship better. That was the biggest letdown for me. TFA suggested that their son’s turning was this drastic emotional break, but here they already feel like a couple who are sliding towards a “our lives just went different ways” amicable divorce.
Catalyst, OTOH….I completely had a different response to Krennic. I *liked* him. Not in necessarily an “I want him to win” way, but an “I can accept this as a believable interesting person” way. He starts out even in at worst anti-villain territory and we get a logical progression of how someone who ISN’T a comic-book supervillain goes from basically reasonable to doing some pretty nasty things without any obvious cackling evil breakdowns or pesudo-mystic stuff (and Pablo is in fact wrong in his tweet about the villains being idiots; while totalitarian *collectivist* states may require/rely on the majority of the ‘worker hive’ being relatively stupid, or rather, deliberately uninformed-see the Soviet Union, Maoist China, etc–while there are dictators who were insane, people running totalitarian states are rarely idiots. Stalin, Castro, Mao in particular, all of whom were outstandingly evil in human history in excess even of the Nazis–they were not idiots, nor were the people working for them. Hitler may have been mentally unstable but he wasn’t stupid, and the people around him were, Himmler and the certifiably-schizoid Hess excepted, quite smart. Speer in particular. On the military end Rommel was a genius the best Allied military commanders respected more than they respected each other. Ones who are genuinely dumb, like Che Guevara, end up dead because they’re out-maneuvered by smarter enemies. Intelligence is completely unrelated to niceness or goodness, also completely separate and in both cases entirely relative values anyway. Plus in fiction, if your villains are dumb, after a while one begins to wonder just how stupid and inept the heroes must be if they’re the underdogs to these guys. And it’s VERY hard to sympathize with the stupid and inept, so if ALL your characters are, well….)
And while I found Lyra far too fluffy-bunny to actually sympathize with, and think she had more than enough page time, she was great because she’s the mother of the protagonist of the new film and the wife of the MacGuffin. In a way she’s the key to those characters, and she’s important because she’s one of the first really good looks with get at a ‘civilian’ view of the Force and the Jedi. I don’t recall ever really getting a pre-ANH character like her before-someone with no political connection, good or bad, to the Jedi, who sees them and the Force differently and without the cynical skepticism of someone like Han in ANH. I’m not really interested in the Clone Wars themselves, but this is getting to a period that IS interesting (the original films) and we do have 19 years to fill there.
I agree with the grade. I was excited for it because, hey, Rogue One tie-in! But the majority of the novel was just backstory/filler that I’m sure will be explained much more succinctly (if it’s even necessary) in the movie.
Two things that did catch my interest were (potential spoilers) how you get a sense of how desperate Krennic is to find Galen again at the end of the novel, as well as how Krennic seems to view Jyn with a mixture of disdain/disgust (at least, that’s the impression I got), which made me wonder how he’ll react to grown-up Jyn (and how she’ll react to him).
The book did get me excited to see the Krennic vs. Tarkin rivalry that will hopefully feature somewhat in the movie, so there’s that. But yeah, nothing truly necessary about it.